Sole for footwear or footwear attachment having multilevel cleats for indicating wear and providing enhanced traction and flexibility

ABSTRACT

A ground engaging portion of an article of footwear for enhancing the traction and flexibility of the ground engaging portion has a plurality of multilevel cleats. The multilevel cleats include a plurality of cleat base elements extending upwardly from a surface thereof to define a first level of the multilevel cleats. A plurality of cleat top elements extend upwardly from a surface of a selected cleat base element to define a second level. The cleat base elements are arranged upon the surface of the ground engaging portion to define both longitudinal and transverse base element grooves therebetween. The cleat top elements are disposed upon a cleat base element to define both longitudinal and transverse top element grooves therebetween.

BACKGROUND OF THE INVENTION

[0001] This application relates generally to footwear and more particularly to a ground engaging portion of an article of primary footwear such as a shoe or a boot, or an attachment device which is adapted to be mounted upon an article of primary footwear so that the ground engaging portion provides enhanced traction between the article of primary footwear and a walking surface and substantial flexibility.

[0002] It is well known in the art to provide a sole having cleats disposed upon its ground engaging portion in order to enhance traction between the sole and a walking surface. Additionally, various attachment devices for primary footwear having cleats disposed upon their ground engaging portions are available for enhancing traction between the primary footwear and a walking surface. Attachment devices bearing spikes are also available to prevent slippage on ice or other slippery surfaces. The known attachment devices can take the form of complex sandals or other devices which are adapted to be mounted upon an article of primary footwear by means of attaching straps or components for engaging the upper of the footwear. Additionally, the attachment devices can take the form of simple pads or strips for securement to the sole of the primary footwear.

[0003] Examples of these devices are found in U.S. Pat. Nos. 1,032,600 (Grout); 2,361,972 (Smith); 3,214,850 (McNair); 3,516,181 (Jordan); 4,344,238 (Peyser); 4,353,172 (Bryant); 4,525,939 (McNeil et al.); and 4,910,883 (Zock, Jr.). Further examples are found in U.S. Pat. Nos. 1,796,399 (Roodhouse); 1,747,603 (Ruth); 1,716,790 (Mitchell); 2,426,524 (Rosenbarger); 2,408,152 (Porcelli); 2,732,065 (Marchese); 2,793,136 (Root); 3,561,140 (Ludwig); 3,903,620 (Gillet); 4,702,021 (Cameron); and 4,924,608 (Mogonye). U.S. Pat. No. 4,271,610 (Parrent) discloses a pad for releasable securement to an article of footwear for adjusting friction. Additionally, copending U.S. patent application Ser. No. 09/378,251 discloses an attachment device having strips of elastic material that form a toe box section and a heel counter section for releasably mounting the attachment device to an article of primary footwear. A ground engaging traction enhancing surface has contoured recessed areas shaped to receive and retain a plurality of hard non-elastic cleats. The attachment device is detachably mounted on an article of primary footwear using straps.

[0004] While the aforementioned prior art devices are generally suitable for their intended purposes, they still leave something to be desired from various standpoints. For example, a common method of increasing the traction provided by the prior art soles and attachment devices is to increase the number of cleats disposed on the ground engaging portion thereof and thereby provide additional gripping points to apply to the walking surface. However, increasing the number of cleats in this manner also increases the rigidity of the ground engaging portion. Increased rigidity due to the presence of a larger number of cleats makes the sole or the attachment device uncomfortable for the user when the user is walking.

[0005] It is known to arrange the cleats on a ground engaging surface in a manner adapted to thereby contribute less rigidity to the ground engaging portion and make the sole or attachment device less uncomfortable for the user. Ground engaging surfaces of this type are shown in the following U.S. Pat. Nos. 767,120 (Pratt), 997,657 (Drake), 1,011,110 (Brown), 1,490,107 (Hale), 2,303,682 (Bullis), 4,194,310 (Bowerman), 4,899,467 (Mackey), 5,282,288 (Henson), 5,293,701 (Sullivan) and 6,101,746 (Evans). These references disclose a plurality of arrangements of cleats on such ground engaging surfaces including arrangements forming flexible grooves for permitting greater flexibility of the surfaces.

[0006] Other prior art attachment devices for footwear are shown in the following U.S. Pat. Nos. 157,985 (Buxton), 913,411 (Marius), 1,299,037 (Runyan), 1,299,650 (Young), 1,433,902 (Masters), 1,518,910 (Gammeter), 1,587,571 (Willis), 1,601,700 (Morrison), 1,716,790 (Mitchell), 1,747,603 (Ruth), 1,877,080 (Teshima), 1,970,254 (Sullivan), 2,076,316 (Beals, Jr.), 2,275,214 (Alvistur), 2,303,744 (Jacobs), 2,327,360 (Margolin), 2,350,362 (Margolin), 2,370,963 (Issaly), 2,387,029 (Kellman), 2,423,753 (Brooks), 2,617,209 (Jackson), 2,628,437 (Forsythe), 3,012,343 (Dinkel), 3,040,451 (Helkemeyer), 3,583,082 (Jordan, Jr.), 3,609,888 (Rickman), 4,302,890 (Covell et al.), 4,727,662 (IIon), 4,807,372 (McCall), 4,924,608 (Mongonye), 5,341,582 (Liautand), 5,485,687 (Rohde), 5,752,332 (Kataoka) and 6,018,889 (Friton). All of the aforementioned ground engaging surfaces also suffer from one or more drawbacks.

OBJECTS OF THE INVENTION

[0007] Accordingly, it is a general object of the invention to provide a ground engaging portion for use on an article of primary footwear, e.g., a boot, shoe, etc., or an attachment device for an article of primary footwear which overcomes the disadvantages of the prior art.

[0008] It is another object of the invention to provide an article of primary footwear or an attachment device for an article of primary footwear for enhancing the traction provided by the ground engaging surface thereof.

[0009] It is yet another object of the invention to provide an article of primary footwear or an attachment device for an article of primary footwear for enhancing the traction of the article of footwear which is simple in construction.

[0010] It is another object of the invention to provide an article of primary footwear or an attachment device for an article of primary footwear including a ground engaging surface having plural cleats or spikes for providing increased traction.

[0011] It is another object of the invention to provide an article of primary footwear or an attachment device for an article of primary footwear having substantial depth recesses or grooves formed therein for providing a traction enhancing, ground engaging surface.

[0012] It is another object of the invention to provide an article of primary footwear or an attachment device for an article of primary footwear having substantial depth recesses or grooves formed therein arranged for providing substantial flexibility of the primary footwear or attachment device.

[0013] It is another object of the invention to provide an article of primary footwear or an attachment device for an article of primary footwear having wear indicating elements for indicating when the ground engaging surface is worn down due to use and requires replacement.

SUMMARY OF THE INVENTION

[0014] These and other objects of the subject invention are achieved by providing a ground engaging portion for a sole or an attachment device for an article of primary footwear, the ground engaging portion having a plurality of multilevel cleats. Generally, the multilevel cleats include a raised base element thereby defining a first level of the multilevel cleat. Plural additional top elements are disposed upon the base element thereby defining a second level of the multilevel cleat. The base elements are disposed on the ground engaging surface in spaced apart locations selected to define both longitudinal base flexing grooves and transverse base flexing grooves therebetween. The longitudinal and transverse base flexing grooves disposed between the base elements are adapted to enhance the flexibility of the ground engaging surface. Furthermore, the top elements are disposed in spaced apart locations upon the surfaces of the base elements selected to define both longitudinal top element flexing grooves and transverse top element flexing grooves therebetween. The longitudinal and transverse top element flexing grooves are adapted to further enhance the flexibility of the ground engaging surface by permitting the base elements to be move flexible. Thus, the invention set forth herein is a ground engaging portion of an article of footwear having longitudinal and transverse axes for enhancing the traction and flexibility of the ground engaging portion, the ground engaging portion having a plurality of multilevel cleats. The multilevel cleats of the plurality of multilevel cleats include a plurality of cleat base elements extending upwardly from a surface of the ground engaging portion and defining a first level of the multilevel cleats and a plurality of cleat top elements extending upwardly from a surface of a selected cleat base element and defining a second level of the multilevel cleats. The cleat base elements are disposed in a spaced apart arrangement upon the surface of the ground engaging portion to define between said spaced apart cleat base elements both a longitudinal base element groove along the longitudinal axis and a transverse base element groove along the transverse axis. The cleat top elements are disposed in a spaced apart arrangement upon a surface of the selected cleat base element to define both a longitudinal top element groove and a transverse top element groove between the cleat top elements. The ground engaging portion is an article of primary footwear or an attachment device for mounting the attachment device upon an article of primary footwear. Two, four or any other number of top elements can extend upwardly from the surface of the cleat base element provided that the longitudinal and transverse flexing grooves are defined therebetween. The surface of the ground engaging portion, the cleat base portions, and the cleat top portions are formed from a resilient material as an integral unit. At least one of the cleat base elements or the cleat top elements is formed in a square, circular, triangular, or any other shape.

DESCRIPTION OF THE DRAWINGS

[0015] Other objects and many attendant features of this invention will become readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

[0016]FIG. 1 is an isometric view of the multilevel cleats of the subject invention disposed upon a ground engaging surface of an article of primary footwear or an attachment to an article of primary footwear;

[0017]FIG. 2 is a plan view of an attachment device in accordance with the subject invention for mounting upon a conventional article of primary footwear; and

[0018]FIG. 3 is a plan view of a sole of a shoe in accordance with the invention (the shoe being shown by phantom lines).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Referring now to various figures of the drawing where like reference numerals refer to like parts there is shown at 10 a ground engaging portion constructed in accordance with the invention. The ground engaging portion 10 is adapted for enhancing the traction and flexibility of articles of footwear such as the sole of an article of primary footwear, e.g., a shoe or a boot (shown in phantom in FIG. 3). The ground engaging portion 10 of the present invention can also enhance the traction and flexibility of an attachment device for mounting on an article of primary footwear (FIG. 2), in order to render it more resistant to slippage on slippery surfaces. The attachment device is mounted to an article of primary footwear using straps as shown in FIG. 2 or in any other manner well understood by those skilled in the art.

[0020] In accordance with the preferred embodiment of the invention the ground engaging portion 10 of either the article of primary footwear or the attachment device includes a plurality of multilevel gripping cleats 14. The multilevel gripping cleats 14 are formed of any hard resilient material such as rubber or synthetic rubber and are adapted to improve the ground engaging traction-enhancing properties of the ground engaging portion 10. The ground engaging portion 10 formed with multilevel gripping cleats 14 is adapted to provide enhanced traction and flexibility in all types of slippery conditions, including wet conditions and smooth ice.

[0021] As best seen in FIG. 1, each of the multilevel gripping cleats 14 includes a cleat base element 16 which extends upwardly from the surface of the ground engaging portion 10 to define a first level of the multilevel gripping cleats 14. The cleat base elements 16 disposed upon the ground engaging portion 10 may be formed in any geometric shape or combination of geometric shapes. For example, the cleat base elements 16 can be formed as circles, squares or triangles.

[0022] The arrangement of the cleat base elements 16 upon the surface of the ground engaging portion 10 is adapted to define both longitudinal base element flexing grooves 22 and transverse base element flexing grooves 24 between the adjacent rows and columns of the base elements 16. The longitudinal base element flexing grooves 22 permit the article of footwear from which the base elements 16 extend to flex more easily along the entire lengths of the base element flexing grooves 22. The easier flexing provided in this manner permits the user to be more comfortable when walking, while also permitting the user to obtain the benefits of a larger number of traction enhancing cleats which would otherwise cause the article of footwear to be more rigid. In a similar manner the flexing of the transverse base element flexing grooves 24 permits the article of primary footwear or attachment to flex more easily along their entire length.

[0023] A portion of a longitudinal base element flexing groove 22 is defined between two transversely adjacent cleat base elements 16. A further portion of the same longitudinal base element flexing groove 22 is defined between the next two transversely adjacent base elements 16 in either direction along the base element flexing groove 22. In the preferred embodiment of the invention the two portions of the longitudinal base element groove 22 defined in this manner are aligned with each other. Because of the alignment in this embodiment the adjacent portions of the longitudinal base element flexing groove 22 can flex cooperatively as the user walks. The cooperation of the groove portions contributes to the flexibility of the article of primary footwear or attachment device upon which the base elements 16 are disposed and permits the use of a larger number of the multilevel cleats 14 and increased traction without causing excessive rigidity.

[0024] Additionally, a portion of a transverse base element flexing groove 24 is defined between two longitudinally adjacent cleat base elements 16. A further portion of the same transverse base element flexing groove 24 is defined between the next two longitudinally adjacent base elements 16 in either direction along the transverse flexing groove 24. The two portions of the transverse base element flexing groove 24 defined in this manner are aligned with each other. Thus, in the preferred embodiment the two portions of the transverse base element flexing groove 24 defined in this manner can flex cooperatively as the user walks. The cooperation of the groove portions further contributes to the flexibility of the article of primary footwear or attachment device upon which the base elements 16 are disposed and permits the use of a larger number of multilevel cleats 14 and increased traction. It will be understood that a large number of such longitudinal and transverse aligned groove portions can be defined and can extend continuously over an entire longitudinal or transverse dimension of the ground engaging portion 10.

[0025] Plural top elements 28 extend upwardly from the top surface of at least one of the cleat base elements 16. In the preferred embodiment of the invention plural top elements 28 extend upwardly from each cleat base element 16. The top elements 28 disposed upon the base elements 16 may be formed in any geometric shape or combination of geometric shapes, e.g., circles, squares or triangles. As the ground engaging portion 10 is worn by a user the top elements 28 wear down. Thus, a user of the ground engaging portion 10 can view the length of the top elements 28 remaining upon the client base elements 16 to determine the amount of wear on the ground engaging portion 10.

[0026] It will be understood that as the length of the top elements 28 decreases due to a user wearing the ground engaging portion 10, the amount of traction enhancement provided by the top elements 28 decreases accordingly. Thus, the user can view the remaining length of the top elements 28, determine the usefulness of the ground engaging portion 10 upon which the top elements 28 are disposed, and replace the ground engaging portion when replacement is thus indicated.

[0027] The arrangement of the top elements 28 is adapted to define both longitudinal top element flexing grooves 30 and transverse top element flexing grooves 32 between adjacent rows and columns of the top elements 28. In the preferred embodiment of the invention the top element flexing grooves 30, 32 extend from each multilevel cleat 14 to its adjacent multilevel cleats 14 along entire longitudinal and transverse dimensions of the ground engaging portion 10.

[0028] The top element flexing grooves 30, 32 permit increased flexibility of the base elements 16 of the multilevel cleats 14 and, hence, increased flexibility of the ground engaging surface upon which the multilevel cleats 14 are disposed. Thus, a greater number of top elements 28 can be disposed on the base elements 16 without excessively increasing the rigidity of the base elements 16, thereby increasing traction while permitting the article of primary footwear or attachment device to be more comfortable for a user when the user is walking. In accordance with the invention, any number of top elements 28 can be disposed upon an individual base element 16 provided that the top elements 28 are arranged to form the top element flexing grooves 30, 32.

[0029] A portion of a longitudinal top element flexing groove 30 is defined between two transversely adjacent top elements 28. A further portion of the same longitudinal top element flexing groove 30 is defined between the next two transversely adjacent top elements 28. In the preferred embodiment of the invention these portions of the longitudinal base element groove 30 are aligned with each other. Thus, in this embodiment the two adjacent portions of the longitudinal top element flexing groove 30 can flex cooperatively as the user walks. Cooperation of the groove portions in this manner contributes to the flexibility of the base elements 16 and, hence, to the flexibility of the article of primary footwear or attachment device upon which the base elements 16 are disposed.

[0030] Furthermore, a portion of a transverse top element flexing groove 32 is defined between two longitudinally adjacent top elements 28. A further portion of the same transverse top element flexing groove 32 is defined by the next longitudinally adjacent top elements 28. Thus, in this embodiment the two adjacent portions of the transverse top element flexing groove 32 can flex cooperatively as the user walks. This also contributes to the flexibility of the article of primary footwear or attachment device as previously described. It will be understood that the adjacent cooperating portions of the top element flexing grooves 30, 32 defined in this manner can be disposed upon a single base element 16 or upon adjacent base elements 16.

[0031] As should be appreciated from the foregoing description the ground engaging portion 10 having the multilevel gripping cleats 14 in accordance with the invention is simple in construction and can be fabricated readily. Moreover, when the ground engaging portion 10 is provided as an attachment device for an article of primary footwear and molded of a resilient material it can be folded or rolled up into a compact configuration. Thus, it can be conveniently stored or transported until the user is ready to wear it. For example, a worker can carry the attachment device either unfolded or folded, unrolled or rolled in his/her pocket. When it is desired to use the attachment device, it can be conveniently retrieved and mounted upon the article of primary footwear.

[0032] Without further elaboration the foregoing will so fully illustrate our invention that others may, by applying current or future knowledge, adapt the same for use under various conditions of service. 

What is claimed is:
 1. A ground engaging portion of an article of footwear having longitudinal and transverse axes for enhancing the traction and flexibility of said ground engaging portion, said ground engaging portion having a plurality of multilevel cleats, the multilevel cleats of said plurality of multilevel cleats including a plurality of cleat base elements extending upwardly from a surface of said ground engaging portion and defining a first level of said multilevel cleats and a plurality of cleat top elements extending upwardly from a surface of a selected cleat base element and defining a second level of said multilevel cleats, the cleat base elements being disposed in a spaced apart arrangement upon said surface of said ground engaging portion to define between said spaced apart cleat base elements both a longitudinal base element flexing groove along said longitudinal axis and a transverse base element flexing groove along said transverse axis, said cleat top elements being disposed in a spaced apart arrangement upon a surface of said selected cleat base element to define between said cleat top elements both a longitudinal top element groove and a transverse top element groove.
 2. The ground engaging portion of claim 1, wherein a selected cleat top element of said plurality of cleat top elements has a starting length prior to said ground engaging portion being used by a user and the length of said selected cleat top element decreases as said user uses said ground engaging portion in accordance with the use of said ground engaging portion.
 3. The ground engaging portion of claim 2, wherein a remaining length of said selected cleat top element is representative of the remaining usefulness of said ground engaging portion.
 4. The ground engaging portion of claim 1, wherein said longitudinal base element groove is adapted to be a flexing groove for increasing the flexibility of said ground engaging portion.
 5. The ground engaging portion of claim 4, wherein said transverse base element groove is adapted to be a flexing groove for increasing the flexibility of said ground engaging portion.
 6. The ground engaging portion of claim 5, wherein said longitudinal and transverse top element grooves are adapted to be flexing grooves for increasing the flexibility of said ground engaging portion.
 7. The ground engaging portion of claim 6, wherein said top cleat elements are disposed in a spaced apart arrangement upon the surfaces of a plurality of said cleat base elements.
 8. The ground engaging portion of claim 7, comprising: (a) a first longitudinal base element groove portion disposed between a first pair of transversely adjacent cleat base elements; (b) a second longitudinal base element groove portion disposed between a second pair of transversely adjacent cleat base elements; and (c) said first and second longitudinal base element groove portions being aligned with each other to permit cooperative flexing of said first and second longitudinal base element groove portions and increase the flexibility of said ground engaging portion.
 9. The ground engaging portion of claim 8, wherein a plurality of said longitudinal base element groove portions are aligned with each other and said plurality of said longitudinal base element groove portions extends over substantially an entire longitudinal dimension of said ground engaging portion.
 10. The ground engaging portion of claim 9, wherein said plurality of said longitudinal base element groove portions extends continuously over substantially an entire longitudinal dimension of said ground engaging portion.
 11. The ground engaging portion of claim 8, comprising: (a) a first transverse base element groove portion disposed between a first pair of longitudinally adjacent cleat base elements; (b) a second transverse base element groove portion disposed between a second pair of longitudinally adjacent cleat base elements; and (c) said first and second transverse base element groove portions being aligned with each other to permit cooperative flexing of said first and second transverse base element groove portions and increase the flexibility of said ground engaging portion.
 12. The ground engaging portion of claim 11, wherein a plurality of said transverse base element groove portions are aligned with each other and said plurality of said transverse base element groove portions extends over substantially an entire transverse dimension of said ground engaging portion.
 13. The ground engaging portion of claim 1, wherein said ground engaging portion comprises an article of primary footwear.
 14. The ground engaging portion of claim 1, wherein said ground engaging portion comprises an attachment device for mounting said attachment device upon an article of primary footwear.
 15. The ground engaging portion of claim 1, wherein two top elements extend upwardly from said surface of said selected cleat base element.
 16. The ground engaging portion of claim 1, wherein four top elements extend upwardly from said surface of said selected cleat base element.
 17. The ground engaging portion of claim 1, wherein said surface of said ground engaging portion, said cleat base elements, and said cleat top elements are formed as an integral unit.
 18. The ground engaging portion of claim 17, wherein said integral unit is formed of a resilient material.
 19. The ground engaging portion of claim 1, wherein at least one of said cleat base elements or said cleat top elements is formed in a square shape.
 20. The ground engaging portion of claim 1, wherein at least one of said cleat base elements or said cleat top elements is formed in a round shape.
 21. The ground engaging portion of claim 1, wherein at least one of said cleat base elements or said cleat top elements is formed in a triangular shape. 